Guantanamo: Honour Bound to Defend Freedom is a play about the British men held without trial at the US military base in Cuba, captives from the early days of the "war on terror".

The writers, Gillian Slovo and Victoria Brittain, say it is "taken from spoken evidence" - what you hear on stage is what was said in letters and interviews by the detainees, their relatives and lawyers.

They depict a crime - or rather, a punishment - so unjust it appears to mock the very liberties the "war on terror" was apparently meant to defend.

The shocking accounts of confinement are more credible now than they may have been even a month ago, before graphic evidence emerged of US troops allegedly torturing Iraqi detainees in Baghdad's Abu Ghraib prison.

Trial run

Even now, there is a feeling that much of what is heard on stage ought to go before a jury, not a theatre audience.

But the US is unlikely to let that happen - it has ruled that its 600-odd captives in Cuba do not enjoy the rights accorded to all prisoners of war under the Geneva Convention.

Donald Rumsfeld... or is it? (photo credit: John Haynes)

Many of them have yet to be tried, despite over two years in prison.

Those trials that do happen are before a special tribunal, without any of the "checks and balances" associated with US military or civilian courts, according to Major Michael Mori, an American military lawyer quoted in the play.

In the absence of these safeguards, the audience plays the role of surrogate jury, watching something closer to testament than theatre.

'Seaside resort'

Detainees and their relatives recount the route to Guantanamo Bay.

The stories are colourful, diverse, exposing the arbitrary logic with which these young Britons - businessmen, seekers and adventurers - found themselves shackled in a series of cages next to the Caribbean Sea.

Jamal al-Harith (Patrick Robinson), one of four British detainees to have been released this year, used to think, "Gosh, I'm from Manchester, what am I doing here?"

Jamal comes across as outspoken (photo credit: John Haynes)

"I'd look at the cage and think, "Is Beadle going to come round or something?" - a reference to the British television prankster, Jeremy Beadle.

Mr Begg (Badi Uzzaman) describes his son, Moazzam, a devout boy from Birmingham who went to Afghanistan as a voluntary aid worker.

Wahab al-Rawi (Aaron Neil) tells of his brother Bisher, a UK resident and motorcycle enthusiast who ended up in Cuba after being arrested on a disastrous business trip to Gambia.

Bisher (Daniel Cerqueira), once a student at an exclusive English school, writes acerbic letters from "the seaside resort of Guantanamo Bay", where he arrived "all expenses paid", "after winning first prize in a competition".

"Everybody is very nice," he says. "The neighbours are very well behaved. The food is first class, plenty of sun and pebbles, no sand I'm afraid."

Cry for justice

But unwitting farce swiftly gives way to the slow, brutal drudgery of prison life.

To the play's organisers - and to Mr Begg, who watched the performance - the British audience is the one that matters most.

As citizens of America's biggest ally in the "war on terror", the British are in a unique position to push for these prisoners' human rights to be restored.

"I seek justice and not forgiveness," Mrs Jahida Sayyadi, Bisher al-Rawi's mother, writes in the programme. "My son has done nothing to be forgiven for."

At least six Britons and UK residents are still being held in Guantanamo Bay.